Means for supplying air to a gas burner



6 M. E. WARD 3,351,118

MEANS FOR SUPPLYING AIR TO A GAS BURNER Filed June 20, .1966

INVENTOR 4142K 5 144mm United States Patent Office 3,351,118 Patented Nov. 7, 1967 3,351,118 MEANS FOR SUPPLYING AIR TO A GAS BURNER Mark E. Ward, Columbus, Ohio, assignor to Midland- Ross Corporation, Toledo, Ghio, a corporation of Ohio Filed June 20, 1966, Ser. No. 558,833 Claims. (Cl. 158-418) ABSTRACT OF THE DESCLOSURE This invention relates to burners for gas or other suitable fuel and, more particularly, to the means for controlling the supply of air to said burners. The burners of this invention are provided with a large single opening at one end thereof through which air is received that is used for combustion. Disposed about the burner is a sleeve that is operative to reciprocate along the axis of the burner and vary the air opening. The sleeve has a longitudinally extending opening confluent with the burner opening through which air may enter, thereby assuring the flame will not be quenched when the sleeve completely covers the opening. The sleeve has a self-locking feature in that its cross-sectional area is elliptical and the minor axes at the ends of the sleeve are rotated relative to one another. Thus, the portions of the sleeve intersected by these axes press against the burner to hold the sleeve in position.

Gas burners are normally provided with means for varying the ratio of air to gas, and, in the case of atmospheric type burners, this means usually consists of some type of an air sleeve that closes an opening in the burner tube. It is necessary that the sleeve be adjustable and have locking means so that once the proper air-fuel ratio is obtained as evidenced by flame color, the burner may be operated Without need of frequent adjustments or inspections. Most of the gas burners of the present art have locking means consisting of a bolt threaded through an opening in the air sleeve and adapted to engage the burner tube, thereby preventing relative movement between the sleeve and the burner. Having a locking means of this type is inconvenient in that a tool is needed to adjust the same and can become a nuisance when the bolt is removed from the opening and becomes misplaced.

Another requirement of the air sleeve is that no matter what position the sleeve may assume, the gas should obtain suflicient air so that the flame does not obtain a yellow coloration, which is occasioned by too rich a gas mixture and results in carbon depositions about the outlet or port of the burner. Needless to say, carbon depositions of this nature are highly undesirable since they tend to restrict the port opening and reduce the effective beat outtlt.

p Another problem associated with gas burners, particularly those burners used in residential furnaces, is that of lint. As air passes through the air opening it tends to deposit flufiy material, referred to as lint, at the sides of such openings. In time and through continuous usage, the lint may build up and actually bridge across an air opening if the same is not sufficiently large. Most burners are provided with a plurality of openings, separated by a structural member, and must have the lint deposits removed before the air-gas mixture is affected to the extent that a yellow flame results.

It is, therefore, an object of this invention to provide a self-locking air sleeve for a gas burner.

It is another object of this invention to provide an air sleeve that supplies a diffusion of air as it enters the burner.

It is still another object of this invention to provide an air sleeve for a gas burner whereby the gas mixture has suflicient air at all times to prevent a carbonizing flame.

It is a further object of this invention to provide an air inlet means for a gas burner that prevents the deposition of carbon.

It is still a further object of this invention to provide a burner and an air sleeve combination that eliminates the problem of lint build-up at the air inlet.

Other and further objects of this invention will be apparent from the following description and claims, and may be understood by reference to the accompanying drawings which, by Way of illustration, show the preferred embodiment of the invention and what is considered to be the best mode of applying the principles of this invention.

In the drawings:

FIG. 1 is a side elevational view of a combination gas burner and air sleeve embodying the principles of this invention.

FIG. 2 is a cross sectional view of the combination of FIG. 1 taken along the lines 2-2.

FIG. 3 is an expanded side elevational view of the air sleeve shown in FIG. 1.

FIG. 4 is a sectional View of the air sleeve taken along the lines 4-4 of FIG. 3.

FIG. 5 is a sectional view of the air sleeve taken along the lines 5-5 of FIG. 3.

Referring now to the drawings, a burner adapted to operate with natural gas or any other suitable fuel is shown generally at 10. The burner comprises a venturi tube 12 having an inlet end, indicated generally at 14, and a discharge port 16 at the opposite end thereof. The venturi tube 12, at a location 17 intermediate its ends, expands vertically and the sides thereof converge as it extends in a direction away from the inlet end 14, thereby forming the discharge port 16. The venturi tube 12 is made of two pieces that are joined together at the top and bottom, 18 and 20 respectively, by one member overlapping the other, thereby forming a ridge at 13 that extends substantially the entire length of the burner and a similar ridge at 20 that extends along the bottom of the tube. In operating position, the mixing tube 1-2 is set at a slight angle relative to the horizontal, which angle is indicated by 0. The input end 14 of the burner 10 has a large opening 26, which opening includes the lower half of a portion of the tube and extends a short distance uninterrupted and with no obstructions. The upper portion 28 of the tube 12 above the opening 26 is: slightly expanded through provision of a step 30, and a pair of transversely aligned ribs 32 depend from the extreme end of the tube to provide means for attachment to a stud 34 that extends from a regulated gas supplying header (not shown).

A generally cylindrical air sleeve 36 is provided about the input end 24 of the tube 12 for reciprocating motion relative to the tube, thereby providing means for controlling the size of the opening 26. The top of the air sleeve 36 has a projecting portion 38 which forms a channel 40 that is adapted to receive the ridge 18 and guide the air sleeve while preventing rotation thereof. Extending longitudinally along the bottom of the sleeve 36 is an opening 42, which opening is flanked by a pair of longitudinally extending flanges 44.

The generally cylindrical air sleeve 36 has a generally oval or elliptical cross section; while this cross sectional shape hereinafter and in the claims will be referred to as elliptical, it is understood that this term is not limited to a mathematically defined ellipse but may, for example, be an oblated circular cross section. More specifically, as viewed from the back of the sleeve, FIG. 4, the sleeve 36 has an elliptical cross section whose axis extends vertiu) cally, as shown at A, whereas when viewed from the front, FIG. 5, the sleeve has an elliptical cross section whose major axis extends horizontally, as shown at B.

In operation, gas is supplied under pressure to the burner, through the stud 34, and inspirates air through the opening 26 as it travels toward the discharge port 16, the air and gas being thoroughly mixed by the time they exit from the venturi tube 12. The supply of air is regulated by the air sleeve 36 which is disposed about the back portion of the tube 12 and adapted to reciprocate along the axis thereof. The presence of the opening 42 allows suflicient air to mix with the gas, even though the sleeve 36 completel} covers the opening 26, so that the flame does not become so rich as to permit carbon deposition. By regulating the size of the opening 42 in accordance with the supply of gas intended to be delivered to the burner, resulting flame may be controlled (there being conventional means for igniting the gas as it leaves the exit, which means is not shown) so that the flames will not become yellow as a result of lack of air or too rich a gas mixture, and will not result in carbon deposition on the surfaces or in the combustion enclosure, even though the air sleeve completely covers the opening 26. The opening 26 is relatively large and is unobstructed by an structural members so that lint that is normally deposited on the burner as the air enters the burner 10 is not able to collect to such an extent that it would materially reduce the area opening or bridge across to block the opening completely.

The flanges 44 that extend longitudinally below the sleeve 36 and on each side of the opening 42 cause the air to enter the burner in a diffused flow rather than being directed directly toward the central axis of the burner 10. It has been found that by so introducing the air, flame pattern and stability are maintained relatively uniformly through the entire range of air sleeve adjustment.

As stated previously, the air sleeve 36 has a variable elliptical cross section, and it is placed upon the burner with that portion of the shutter whose major transverse axis B is across the horizontal placed toward the exit port 16. With this structure of air sleeve 36, it has been found that the same can be moved forward (to the right, as shown in FIG. 1) rather readily, but greater force is needed to push the sleeve in a reverse direction. Consequently, the air sleeve 36 acts as a self locking device which resists movement in one direction. The burner 10 is placed at a slight angle relative to the horizontal so that the air sleeve 36 has to be moved in an upper direction to be moved forward. Thus the air sleeve 36 has been found to remain stationary while the burner is operating because of the self locking features that prevent it from moving in one direction and the inclined angle that prevents it from moving in the other. Obviously, the tube may be inclined in the opposite direction, i.e. downward, and the air shutter would be reversed so that the side with the vertical transverse axis A would be placed on the tube first.

While only a single embodiment of this invention has been shown and described, it is understood that many changes can be made therein without departing from the scope of this invention, as defined by the following claims:

I claim:

1. The combination of a gas burner and an air sleeve sleeve comprising, a venturi tube having an inlet end and a discharge end, an axially extending tube opening in the proximity of said inlet end, said opening including a substantial portion of the tube circumference at said proximity, a generally cylindrical air sleeve disposed about said tube for reciprocating movement relative thereto, said sleeve having an opening extending the length thereof, said sleeve opening being confluent with said tube opening, a pair of flanges attached to and extending radially from said sleeve, and said flanges being disposed one on each side of said sleeve opening, wherein one end of said air sleeve has an elliptical cross section with a first minor axis and the opposite end of said air shutter has an elliptical cross section with a second minor axis that is rotated at an angle relative to said first minor axis, whereby the portions of the sleeve intersected by said axes press against said venturi tube and form a means for holding the sleeve in position on said venturi tube.

2. The combination of claim 1 wherein said angle is substantially 3. The combination of claim 2 wherein said tube is placed at an angle relative to the horizontal.

4. The combination of a gas burner tube and an air sleeve comprising a venturi tube having an inlet end and a discharge end, an axially extending tube opening in the proximity of said inlet end, said opening including a substantial portion of the tube circumference at said proximity, a generally cylindrical air sleeve disposed about said tube for reciprocating movement relative thereto, said sleeve having an opening extending the length thereof, said sleeve opening being confluent with said tube opening, one end of said sleeve having an elliptical cross section with a first minor axis and the opposite end of said air sleeve having an elliptical cross section with a second minor axis that is rotated about the axis of the cylindrical tube at an angle relative to said first minor axis, whereby the portions of the sleeve intersected by said axes press against said venturi tube and form a means for holding the sleeve in position on said venturi tube.

5. The combination of claim 4 wherein said angle is substantially 90.

References Cited UNITED STATES PATENTS 1,200,078 10/1916 Chambers et al. 1581 18 2,014,665 9/1935 Palmer 158--118 X FOREIGN PATENTS 215,004 10/ 1909 Germany. 368,886 2/1923 Germany. 142,159 5/1920 Great Britain.

FREDERICK L. MATTESON, 111., Primary Examiner.

H. B. RAMEY, Assistant Examiner. 

1. THE COMBINATION OF A GAS BURNER AND AN AIR SLEEVE SLEEVE COMPRISING, A VENTURI TUBE HAVING AN INLET END AND A DISCHARGE END, AN AXIALLY EXTENDING TUBE OPENING IN THE PROXIMITY OF SAID INLET END, SAID OPENING INCLUDING A SUBSTANTIAL PORTION OF THE TUBE CIRCUMFERENCE AT SAID PROXIMITY, A GENERALLY CYLINDRICAL AIR SLEEVE DISPOSED ABOUT SAID TUBE FOR RECIPROCATING MOVEMENT RELATIVE THERETO, SAID SLEEVE HAVING AN OPENING EXTENDING THE LENGTH THEREOF, SAID SLEEVE OPENING BEING CONFLUENT WITH SAID TUBE OPENING, A PAIR OF FLANGES ATTACHED TO AND EXTENDING RADIALLY FROM SAID SLEVE, AND SAID FLANGES BEING DISPOSED ONE ON EACH SIDE OF SAID SLEEVE OPENING, WHEREIN ONE END OF SAID AIR SLEEVE HAS AN ELLIPTICAL CROSS SECTION WITH A FIRST MINOR AXIS AND THE OPPOSITE END OF SAID AIR SHUTTER HAS AN ELLIPTICAL CROSS SECTON WITH A SECOND MINOR AXIS THAT IS ROTATED AT AN ANGLE RELATIVE TO SAID FIRST MINOR AXIS, WHEREBY THE PORTIONS OF THE SLEEVE INTERSECTED BY SAID AXES PRESS AGAINST SAID VENTURI TUBE AND FORM A MEANS FOR HOLDING THE SLEEVE IN POSITION ON SAID VENTURI TUBE. 